• Skou *• has described an adenosine triphosphatase (ATPase) present in crab nerve that is activated by magnesium, sodium, and potassium. A similar enzyme, which is inhibited by cardiac glycosides, was found in the membranes of erythrocytes by Post et al. Hajdu and Szent-Gyorgyi have suggested that the cardiac glycosides exert their positive inotropic effect on the heart through interference wi...

Laboratories performing analyses for serum cardiac glycosides are sometimes faced with the problem of distinguishing between digoxin and digitoxin in a specimen. The antibodies to the cardiac glycosides supplied with radioimmunoassay kits for these drugs have some measurable degree of cross reactivity. Therapeutic levels of digitoxin are approximately ten times greater than those of digoxin, an...

Laboratories performing analyses for serum cardiac glycosides are sometimes faced with the problem of distinguishing between digoxin and digitoxin in a specimen. The antibodies to the cardiac glycosides supplied with radioimmunoassay kits for these drugs have some measurable degree of cross reactivity. Therapeutic levels of digitoxin are approximately ten times greater than those of digoxin, an...

Inhibition of Na,K-ATPase 2 isoforms in the human heart is supposed to be involved in the inotropic effect of cardiac glycosides, whereas inhibition of 1 isoforms may be responsible for their toxic effects. Human Na,K-ATPase 1 and 2 isoforms exhibit a high ouabain affinity but significantly differ in the ouabain association and dissociation rates. To identify the structural determinants that ar...

From the MeOH extract of the leaves of Digitalis viridiflora five phenylethanoid glycosides (1-5) including a new one were isolated. The structure of the new compound was established as 3,4-dihydroxy-βphenylethoxy-O-β-quinovopyranosyl-(16)-4-O-caffeoyl-β-glucopyranoside (viridifloroside, 1) based on extensive 1Dand 2D-NMR spectroscopy as well as MS. Compound 1 is the first example of a phenyle...

[This corrects the article DOI: 10.1371/journal.pone.0162243.].